Cutter chain and cutter bar



Dec. 6, 1938.

R. K. JEFFREY CUTTER CHAIN AND CUTTER BAR I 7 Original Filed June 8,1934 i NK F E N w ATT'Y's.

Patented Dec. 6, 1938 PATENT OFFICE CUTTER CHAIN AND CUTTER BAR RobertK. Jeffrey, Columbus, Ohio, assignor to The Jeffrey ManufacturingCompany, a corporation of Ohio Application June 8, 1934, Serial No.729,704 Renewed February 8, 1936 2 Claims.

The present invention relates to a cutter chain and cutter barparticularly adapted for use in a mining machine.

Objects of the invention are, to provide a cutter chain and a cutter barfor guiding the movement of the same which may be used in the cutting ofa relatively narrow kerf, the cutter bar being so designed that thepossibilities of binding in the kerf will be reduced; and to provide acutter chain having, links so designed with respect to each other as toresist any tendency of the links toward tilting or turning upona'transverse axis.

Other objects and advantages of the invention will be apparent from thefollowing drawing, wherein like numerals refer to similar partsthroughout the several views.

In the drawing:-

Figure 1 is a side elevation of a portion of the cutter chain;

Figure 2 is a transverse sectional view taken on the line 2-2 of Figure1 and showing the cutter bar and the chain;

Figure 3 is a transverse sectional view on the line 3--3 of Figure 1;

Figure 4 is a side elevation of one of the bit carrying links of thecutter chain; and

Figure 5 is a side elevation of one of the connecting links used in thechain.

The numeral Ill designates the bit carrying links which are joined toform a cutter chain by means of connecting links H. The bit carryinglinks [0 are of the bridged type, that is, as shown in Figure 3, theyare substantially U- shaped in cross section, including side bars. orplates l2 integral with a bridging portion l3. Each link [0 is providedwith a projection o-r lug l4 extending outwardly from the bridgingportion l3 and in which a cutter bit l5 may be clamped in any suitablemanner. As is customary, the cutting bits of adjacent links l0 mayproject therefrom at various angles, as shown in Figure 2, in order tocut a kerf of the desired width.

A pair of connecting links H is provided to join adjacent bit carryinglinks In, the links H of each such pair being within the side bars [2 ofthe bit carrying links and having their inner faces spaced apart topermit the chain to straddle the cutter bar I 6. As best shown in Figure2, the links I 0 and II are pivotally connected by a rivet or the like[1, which rivet or other securing member passes through the aperture ateach end of the plate or bar [2 of the bit carrying link [0 and extendsinto the aligned aperture at the near end of the adjacent connectinglink II.

The cutter bar It upon which the chain moves is formed of outer plates2| and an inner T- shaped plate 22, the T-shaped plate 22 extending pastthe outer ends of the plates 2! so that its head 23 is spaced from theplates 2!. As shown in Figures 1 and 3, the bit carrying links it areprovided on the inner walls of their side bars l2 with projections orlugs 24, the outer faces 25 of the projections 24 being straight or flatin a transverse direction, as shown in Figure 3, but the ends of thesesurfaces preferably being rounded as shown in Figures 1 and 4. Thesurfaces 25 are intended to be opposed to the inner surfaces of the head23 of the cutter bar 16. The outer edges 26 of the connectinglinks H arealso opposed to the inner surfaces of the head 23 on each side of thelatter, thereby maintaining the chain in proper pcsitionwith respect tothe cutter bar I6. The plate 22 may be of hardened steel to make it wearresistant.

The inner surface of the lugs 24 may be cut away as shown in Figure 3 topermit fines to drop from the chain.

As best shown in Figure 2, the spacing between the inner surfaces of thehead 23 of the cutter bar and the outer ends of the plates 2| forms agroove along each lateral surface of the cutter bar and the width ofthis groove is substantially the same as, or somewhat greater than, thewidth of the connecting links II and the distance from the inner edgesof the side bars l2 of the links H) to the outer surfaces 25 of theprojections 24 on these latter links.

The provision of a cutter bar straddled by the cutter chain enables theentire structure to be of minimum thickness in a plane at right anglesto the plane of the cutter bar, as: shown in Figure 2, so that when akerf is cut, only a relatively small quantity of coal will be mined asslack. Also, the substantial distance indicated at A in Figure 2 betweena wall of the cutter bar and the adjacent wall of the kerf insures that,even with a narrow kerf, the movement of the cutter bar will not becramped.

. It will also be observed that because the cutter chain straddles thecutter bar instead of moving within the cutter bar, as in the usualconstruction, the dead area of the cutter bar will be reduced. That isto say, by having the chain straddle the bar, the dead or non-movingarea of the bar is reduced and replaced by an increased exposed area ofmoving chain. A moving element such as the chain will not bind in thekerf and by increasing the area of the moving element exposed in thekerf and at the same time decreasing the exposed area of the non-movingmember, the cutter bar itself, the possibility of binding of the cutterbar in the keri' is correspondingly reduced.

The inner surface 21 of the bridging portion l3 of the bit carryinglinks In may be arcuate, as shown, in order to permit these links tomove about the usual curved end of the cutter bar l6.

As is shown in Figures 1 and 5, lugs 28 are provided on the outersurfaces of the connecting links I I, preferably between their ends, theouter surfaces of these lugs being flush with the outer edges 26 of theconnecting links. Shoulders 29 are provided at the ends of the bitcarrying links l0, and as shown. in Figure 1, these shoulders areintended to contact with the outer surfaces of the lugs 28. By thisarrangement, should one bit carrying link In tend to tilt or turn. upona transverse axis, that is, rise at an angle to the cutter bar l6 byreason of engagement of its bit l with the coal, the shoulder 29 at theend of the bit which tends to move inwardly will contact with the lug 28carried by the adjacent connecting link. The connecting link willtherefore resist the tilting of the bit carrying link. As is best shownin Figure l, the ends 30 of the bit carrying links are closely adjacenteach other and are of substantial thickness. Therefore, when aconnecting link tends to tilt, its tilting action will also be resistedby the adjacent bit carrying links as well as by the shoulders 28 on theconnecting links.

By the above arrangement, a sharp tendency of one link to tilt will betransmitted through a number of adjacent links so that each link in theseries affected will act to distribute the tendency to tilting and thelength of chain involved in this action will remain substantiallystraight or stlfi-backed.

It will be understood that the invention is not limited to the detailsof construction shown in the drawing and described in the specificationand that the example of the use of the invention which has been. givendoes not include all the uses of which it is capable; also, that thephraseology employed in the specification is for the purpose ofdescription and not of limitation.

I claim:-

1. In a kerf-cutter for mining machines, the combination with a cutterbar having an outwardly extending rib less in thickness than the body'of the cutter bar to afford shoulders on opposite sides of the cutterbar along the outer edges thereof and along the curved outer edgesthereof in parallelism with the outer edge of the rib, and a chaincutter comprising bit carrying links each comprising spaced straps withcurved surfaces adapted to move along said shoulders including the outercurved ends thereof, said straps being connected by a member havingspaced straight surfaces connected by a curved surface, said straightsurfaces being adapted to ride along the outer lateral edges of the riband said curved surfaces between said straight surfaces being adapted toride along the curved outer end of said rib.

2. In a kerf-cutter for mining machines, the combination with a cutterbar having an outwardly extending rib of less thickness than the body ofthe cutter bar, the outer end of the cutter bar including said rib beingcurved, and a chain cutter comprising bit carrying links each U- shapedto straddle said rib and each having inner spaced straight surfacesconnected by a curved surface, the straight surfaces being adapted toride along the lateral edge of the rib and the curved surface beingadapted to ride along the outer curved end of the rib.

ROBERT K. JEFFREY.

